The invention relates to an optical transmission system, comprising an optical wave guide fiber and a coupling element for coupling the optical waveguide fiber to a light source or to a light detector or to a further fiber. The coupling element includes a lens which is arranged in front of one end of the fiber, and fiber and the lens have optical axes substantially in common. The invention also relates to a coupling element for the optical transmission system and to a lens for the coupling element.
An optical transmission system is described on pages 341 to 359 of "Phatonics", published by Balkanski and Lallemand, 1973. In this publication light is radiated into the core of a fiber via a system of lenses arranged in front of an end face of the fiber. The lenses of the system of lenses must be accurately positioned and oriented relative to the core of the fiber, relative to the semiconductor layer junction shown, and relative to each other.
Notably the axes of the optically cylindrical lenses must intersect the center of the fiber core and should be situated in the plane of the laser junction. The mounting of the lenses in the correct position in front of the end face of the fiber is difficult.